Due to extremely severe cuts in budget and staffing, no progress was made on this research project during the reporting period. This is unfortunate, as this project had been - in previous years - one of our most productive research endeavors, resulting in a large number of publications in the peer-reviewed scientific literature. We are presently pursuing external research collaborations, especially with entities within the pharmaceutical industry, that may allow us to once again pursue this work and follow up on the promising findings that we had obtained in previous years on this project.